Hot workable bronze



Patented Jan. 18, 1938 UNITED STATES PATENT OFFICE HOT WORKABLE BRONZE No Drawing. Application October 31, 1936, Serial No. 108,615

5 Claims. (01. 75-154) This invention relates to copper-tin alloys, and more particularly to a phosphor bronze or other deoxidized copper-tin alloy, and has for an object to produce such an alloy which is hot work- 6 able.

The so called phosphor bronzes are alloys of copper and tin deoxidized with phosphorus before pouring or casting the molten metal into suitable molds. In order to make sure the metal is prop- 10 erly deoxidized there is usually sufiicient of the deoxidizer used so that there is a small surplus and a small amount of the deoxidizer remains in the resulting alloy.

Silicon bronzes are copper-tin alloys deoxidized 1 with silicon before pouring or casting the metal in suitable molds.

Other deoxidizers are also used for deoxidizing the bronzes or copper-tin alloys, but phosphorus is the usual deoxidizer for the tin bronzes.

The present invention or discovery is applicable to all the tin-bronzes within the ranges noted herein whether they are deoxidized with phosphorus, silicon or the other suitable deoxidizers.

All of these bronzes may be cold rolled up to 25 about 12% tin content. These bronzes as a rule also may be hot rolled or worked up to about 2% tin content, but the hot rolling, or hot working, becomes rapidly impossible as the tin content is increased over 2%.

I have found that by adding a suitable amount of manganese to the alloy that the hot rolling and hot working characteristics can be greatly improved. That is, a tin-bronze that could not be hot rolled at all can be easily hot rolled with this addition. This efiect is secured in these coppertin alloys with a tin content of from 2% to 20%, and balance principally copper. The smallest amount of manganese required to give a material improvement in the hot rolling characteristics is about 0.1% and it may be used upto about 5% depending on the amount of tin. The amount of deoxidizer, such for example as phosphorus, silicon, etc. may be from to about 1% in the finished alloy.

It will be appreciated a large number of specific alloys may be made within the ranges of elements noted, but an example of an alloy that hot rolls very nicely has approximately the following proportions: tin manganese 0.5%, phosphorus 0.1%, and balance copper.

The manganese content, however, may be varied so that these alloys ranging from 2% to tin may be readily hot rolled or otherwise hot worked. The preferred amount of mangal5 nese ranges from 0.25% to 0.75% as this amount gives the desired effect and it is preferred not to use more manganese than necessary. However, the manganese content may be as high as 5% if desired. 20

Having thus set forth the nature of my invention, what I claim is:

1. An alloy composed of approximately 5% tin, 0.5% manganese, and balance copper.

2. A deoxidized copper base alloy composed of 2% to 20% tin, 0.25% to 0.75% manganese, and balance copper.

3. A phosphor bronze characterized by being hot workable containing 2% to 20% tin, 0.25% to 0.75% manganese, and. balance copper.

4. An alloy composed of from 2% to 20% tin, from 0.25% up to less than 5% manganese and balance copper, which is characterized by being hot workable.

5. An alloy composed of 2% to- 20% tin, from 0.25% to 0.75% manganese, and balance copper which is characterized by being hot workable.

DANIEL R. HULL. 

